a Cells

The a cells are another group of cells located within the pancreas. Instead of producing insulin, they produce another vital hormone known as glucagon. They make up approximately 25 to 30% of the cells in the islets of langerhans within the pancreas. The main function of glucagon is the reverse of insulin, that of raising blood sugar. It does this by binding to liver and muscle cells and cauing them to break down glycogen into glucose which can then be used to produce energy. This is a process known as glycogenolysis.